Pyridoxal 5-Phosphate (PLP), Plasma

B6 (Vitamin); PALP (Pyridoxal 5-Phosphate); Pyridoxal 5-Phosphate (PALP); Pyridoxal Phosphate; Vitamin B6

Labcorp

Useful for:

• Determining vitamin B6 status, including in persons who present with progressive nerve compression disorders, such as carpal tunnel and tarsal tunnel syndromes


• Determining the overall success of a vitamin B6 supplementation program


• Diagnosis and evaluation of hypophosphatasia

Lavender-top (EDTA) tube; amber plastic transport tube with amber-top. (If amber tubes are unavailable, cover standard transport tube completely, top and bottom, with aluminum foil. Identify specimen with patient's name directly on the container AND on the outside of the aluminum foil. Secure with tape.) For amber plastic transport tube and amber-top, order LabCorp item No. 23594.

Plasma (EDTA), PROTECTED FROM LIGHT

Green Top (sodium or lithium heparin)

• Patient Preparation:
  
  
  
  • Fasting-overnight (12-14 hours) (infants-draw prior to next feeding)
  
  
  • Patient must not ingest vitamin supplements for 24 hours before the specimen is drawn
  
  
  • Centrifuge at 4 degrees C within 2 hours of collection, then aliquot all plasma into amber vial.
  
  
  
  

0.5 mL

Ship specimen in amber vial to protect from light

Refrigerated or FROZEN and PROTECT FROM LIGHT.

Stable Room Temperature: 3 Days
Stable Refrigerated: 15 Days 
Stable Frozen: 15 Days

Refrigerated specimens

Reference ranges were established using healthy fasting volunteers who abstained from vitamin supplementation for 24 hours prior to collection. Vitamin supplementation and nonfasting may result in elevated plasma vitamin concentrations

Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

1-4 days

Monday-Friday

84207

5-50 mcg/L

30552-4

Test Definition: PLP